General Model of Railway Transportation Capacity

Transcription

1 General Model of Railway Transportation Capacity Hans E. Boysen, Lic.Eng. Department of Transport Science Royal Institute of Technology

2 Outline MODEL CASE STUDY #1: TRACK UPGRADE CASE STUDY #2: SPEED INCREASE RECOMMENDED BEST PRACTICE

3 Background Capacity is often discussed merely as the number of trains that can be accommodated under given constraints. But, there is more to it! TRV

4 Model Objectives To identify: main system features that determine freight transportation capacity, interdependencies between features. To quantify: magnitude of realizable improvements, effects of trade-offs.

5 The Mission The mission of transportation: moving goods (or passengers).

6 The Product The product moved goods (or passengers) can be quantified as distance amount.

7 The Product Why multiply (distance amount)? Because alternative production schemes, limited by main asset constraints, produce the same end state. E.g. half the load at twice the speed, requiring twice the trips, completed in the same time, limited by the same tractive power (P = F v). Approximately. (It s not all linear.)

8 Productivity Productivity is product in relation to limited resources used, e.g. time: distance amount / time Re-write as: or distance / time speed amount amount where amount is characterized as mass or volume.

9 Production System Main production system assets: Infrastructure network with links and nodes Vehicle consists (trains) Crews Plans and controls

10 Infrastructure vs. Train Operations (Fixed vs. Moving Assets) Infrastructure network perspective Yard throughput capacity: Wagons/ day Wagon capacity Link throughput capacity: Trains/ day Train capacity Train operating perspective Production capacity: Speed Train capacity

11 Distance The Role of Speed Mixed traffic consumes available capacity Time Time while homogenous traffic at uniform speed can run at high frequency.

12 General Model of Transport Capacity Infrastructure Perspective Mass transport capacity (high density goods) Trains/ day Train length Meter load Payload/ gross mass Fill rate (back hauls) Train gross wagon mass Volume transport capacity (low density goods) (utilization) Trains/ day Train length Length utilization Useful cross section Fill rate (back hauls)

13 General Model of Transport Capacity Train Operating Perspective Mass transport capacity (high density goods) Speed Train length Meter load Payload/ gross mass Fill rate (back hauls) Train gross wagon mass Volume transport capacity (low density goods) (utilization) Speed Train length Length utilization Useful cross section Fill rate (back hauls)

14 Mass Transport Capacity 100/ / / / /250 ETCS3 1.3 ETCS2 1.0 ATC2 1.0 DT 262/direction DT ST ST 98 1 Trains/ day km/h > Train length m Meter load 4 40t-22.7t = t t/m = Payload/ gross wt =0.80 =0.71 = Fill rate (back hauls) 8200 t (automatic couplers) 4000 t (screw couplers) 2500

15 100/ / / / /250 ETCS3 1.3 ETCS2 1.0 ATC2 1.0 DT 178 ST 193 ST 98 Trains/ day Volume Transport Capacity km/h DT 262/direction > Train length m 22m/23.26m= /15.14= /34.03= /18.34=0.74 Length utilization IN-DFC US-DS AAR K SE-C AAR F FI-KU UIC GC P 450 SE-A P 400 DE-G2 DE-G Useful cross section* m Fill rate (back hauls) *inscribed rectangle above floor level

16 Capacity Increase 30 % Each Mass transport capacity (high density goods) T+ ETCS3 V- Trains/ day m m Train length Meter load Load ratio Fill rate (back hauls) 5200 t Volume transport capacity (low density goods) T+ ETCS3 V- Trains/ day m m Train length Length utilization Flat top Useful cross section Fill rate (back hauls)

17 Interdependencies Some factors are effective only in combination, e.g.: long trains are useful only with a high mass limit, large loading gauges are useful only for low-density commodities, high meter loads are useful only with a high mass limit and with a large loading gauge or high-density commodities.

18 Conclusions To achieve large capacity increases ( 30%) compared to the present, these factors are broadly effective: - homogeneous speed, ETCS3 signaling, number of tracks, train length, loading gauge, train mass. For specific commodities, these can also be effective: - meter load, axle load. Some factors are effective only in combination. Effectiveness must be considered in relation to cost. Small increases are also worthwhile, if easy to implement.

19 Commodity Mix Sweden 2010 Tonnage share by commodity group 2010 Data: TA Ores Unidentifiable goods Agriculture, forestry and fishing products Wood, pulp and paper Metal products Secondary materials Coke and refined oil Transport equipment, empty containers Chemical products Transport equipment, automobiles Non-metallic minerals Food and beverages Coal, crude oil and gas Machinery Furniture Consolidated goods Textile and leather products Summary: The big 5: ores, unidentifiable, logs, forest, metal products.

20 Commodity Mix Sweden 2010 Ton-km share by commodity group 2010 Data: TA Unidentifiable goods Ores Metal products Wood, pulp and paper Agriculture, forestry and fishing products Secondary materials Transport equipment, empty containers Chemical products Coke and refined oil Transport equipment, automobiles Food and beverages Non-metallic minerals Coal, crude oil and gas Machinery Furniture Consolidated goods Textile and leather products Summary: The big 5: intermodal, ores, metal products, forest, logs.

21 Case Study #1 Track Upgrade The railway was strengthened from 25 to 30 tons axle load (metric), i.e. +20 %. How much did transportation capacity change due to the higher axle load?

22 Case Study #1 Track Upgrade LKAB

23 Case Study #1 Track Upgrade System constraints after upgrade Axle load: 25 tons 30 tons (metric) axle load wagon tare Wagon payload - old wagon: (4 25 t)-20 t = 80 tons - new wagon: (4 30 t)-21.4 t = 98.6 tons Wagon load ratio, payload-to-gross mass - old wagon: (4 25 t-20 t)/(4 25 t) = new wagon: (4 30 t-21.4 t)/(4 30 t) = 0.82

24 Case Study #1 Track Upgrade Old wagon Marley

25 Case Study #1 Track Upgrade New wagon LKAB

26 Case Study #1 Track Upgrade System constraints after upgrade Lengths - train: 750 m (due to sidings) - locomotives: m 45.8 m - total wagons: 750 m 45.8 m = m - old wagons: 8.4 m - new wagons: 10.3 m Meter loads - track limit: 12.0 tons/m (due to bridges) - old wagons: 4 25 tons / 8.4 m = tons/m - new wagons: 4 30 tons / 10.3 m = tons/m

27 Case Study #1 Track Upgrade Analysis Apply the transportation capacity model!

28 General Model of Transport Capacity Infrastructure Perspective, Case #1 Mass transport capacity (high density goods) Trains/ day Wagon length Meter load Total wagon gross mass Payload/ gross mass With 25 tons axle load 704 m t/m (4 25t-20t)/ (4 25t)=0.800 = 6702 t With 30 tons axle load 704 m 8378 t t/m net/gross ratio: +2.8% (4 30t-21.4t)/ (4 30t)=0.822 train payload: +0.6% = 6742 t 8202 t Payload/train unchanged.

29 Case Study #1 Track Upgrade Possible conclusion #1: Train load capacity increased by +0.6 %. But

30 Case Study #1 Track Upgrade Speed was also changed: - loaded 50 km/h 60 km/h, % - empty 60 km/h 70 km/h, % Apply the transportation capacity model again!

31 General Model of Transport Capacity Train Operating Perspective, Case #1 Mass transport capacity (high density goods) Speed Wagon length Meter load Payload/ gross mass With 25 tons axle load 50 km/h Total wagon gross mass 704 m t/m (4 25t-20t)/ (4 25t)=0.800 = tkm/h 8378 t With 30 tons axle load 60 km/h 704 m t/m transportation capacity: +20.7% (4 30t-21.4t)/ (4 30t)=0.822 = tkm/h 8202 t Transportation capacity significantly raised.

32 Case Study #1 Track Upgrade Was the speed increase due to the axle load increase? If so, possible conclusion #2: System transportation capacity changed by % as a result of the track upgrade.

33 Case Study #1 Track Upgrade Possible conclusion #3: Axle load and meter load should have been raised together.

34 Rail Freight Corridors 2020 Narvik Scandria corridor Rail ferry link Marshalling yard Luleå Skellefteå Oulu Trondheim Östersund Vännäs Örnsköldsvik Umeå Rail Freight Corridors 2020 Bergen Stavanger Taulov Drammen Århus Oslo Göteborg Odense Trollhättan Ålborg Halmstad Helsing - borg Køben - havn Skövde Varberg Jönköping Sundsvall Falun Gävle Borlänge Uppsala Västerås Örebro Hallsberg Ånge Nässjö Älmhult Lund Malmö Trelleborg Katrineholm Norrköping Linköping Tampere Turku Stockholm Riihimäki Kouvola S:t Petersburg Helsinki Tallinn Riga Hamburg Rostock Sassnitz Berlin

35 Case Study #2 Speed Increase If the speed of intermodal trains is raised from 100 to 120 km/h, how will this affect the system transportation capacity?

36 Case Study #2 Speed Increase Two capacity trade-offs exist with permissible speed: - speed vs. load limit per wagon - speed vs. train length. Both trade-offs are due to brake system performance. Apply the transportation capacity model!

37 Case Study #2 Speed Increase Green Cargo Ruud Intermodal wagon, Sdggmrs Intermodal wagon, Sdggmrss

38 Case Study #2 Speed Increase Speed vs. load limit per wagon (Sdggmrss-t) A B C D 100 km/h S 61 t 73 t 88 t 100 t wagon payload: 120 km/h SS 61 t 73 t 85 t -15% Legend Track axle load limit: A=16 t, B=18 t, C=20 t, D=22.5 t Wagon speed limit: S=100 km/h, SS=120 km/h Wagon load limit: t Limited by braking performance and signal distance.

39 Case Study #2 Speed Increase Speed vs. train length (Denmark) Speed (km/h) Train length (m) train length: -28% Limited by braking performance and signal distance.

40 General Model of Transport Capacity Infrastructure Perspective, Case #2 Mass transport capacity (high density goods) Trains/ day Wagon length Meter load Total wagon gross mass Payload/ gross mass With 100 km/h speed 816 m 2.94 t/m (6 22.5t-35t)/ (6 22.5t)=0.741 = 1776 t With 120 km/h speed 581 m 2398 t 2.50 t/m (6 20t-35t)/ (6 20t)=0.708 train payload: -42% = 1028 t 1451 t Payload/train significantly reduced.

41 General Model of Transport Capacity Train Operating Perspective, Case #2 Mass transport capacity (high density goods) Speed Wagon length Meter load Payload/ gross mass Total wagon gross mass With 100 km/h speed m km/h 2.94 t/m (6 22.5t-35t)/ (6 22.5t)=0.741 = tkm/h 2398 t With 120 km/h speed 120 km/h 581 m 2.50 t/m transportation capacity: -30.5% (6 20t-35t)/ (6 20t)=0.708 = tkm/h 1451 t Transportation capacity significantly reduced.

42 Case Study #2 Speed Increase Conclusion: Case Study #2 was instrumental in convincing Denmark not to require a ban on 100 km/h freight trains in the planning for the new Fehmarn Belt tunnel Denmark Germany.

43 Recommended Best Practice Europe Freight train speed Train length -Head end loco -Rear end brake -Distributed locos Wagon mass -Head end loco -Distributed locos Distant signals Loading gauges Intermodal gauges Meter load Axle load Gradient Wagon brake ratio Screw coupler strengths 120 km/h (day), 100 km/h (night) 730 m (P), 835 m (5GP), 880 m (G) 1440 m (P), 1650 m (5GP), 1740 m (G) 1440 m+730 m (P), 1740 m+880 m (G) 5200 tons on 10 (screw couplers) 5200 tons+5200 tons (screw couplers) 1200 m 3.15 m, 3.40 m, 3.60 m 4.90 m flat top 2.60 m 4.33 m, 2.60 m 4.83 m (P/C 450) 8.3 tons/m (4 25 tons/12 m) 25 tons % ( SS) 0.85 MN, 1.35 MN

44 Desired Loading and Intermodal Gauges OHL 5.30 m Clearance 0.40 m (25 kv) Wide 3.60 m 4.90 m P/C m 4.83 m Medium 3.40 m 4.90 m P/C m 4.33 m Narrow 3.15 m 4.90 m TOR 0.00 m Pocket 0.33 m

45 Ongoing Work Systematic application to seven main commodities to use recommended infrastructure and operating best practice. Re-designing wagons. Re-designing train consists. Maximising capacity and operating efficiency. Searching for step changes: small changes with big pay-offs.

46 Thank you!